Typically, as a harvester combine moves forward through a crop such as wheat, the wheat is cut and conveyed upwardly into the combine and into a threshing portion thereof where the grain is separated from the wheat stalks and then conveyed by the combine to a series of sieves where the chaff is blown away from the grain by blasts of air. The grain separated from the chaff is conveyed within the combine to a grain chute, while the crop residue, including the straw stalks and chaff, is typically conveyed or blown rearwardly to be discharged from the combine through a rear output port. In the absence of some mechanism for broadcast spreading the crop residue, it will typically fall into elongated piles or a windrow trailing behind the combine.
In some instances, when the user desires to make further use of the crop residue, distribution of the crop residue in a windrow may be preferred and the user may then bale or otherwise remove the windrowed material from the field. In other instances, the user does not desire to so make use of the crop residue, and discharge of the crop residue in a windrow is not preferred. In such instances, users generally desire that the crop residue be spread in a swath over a field, and be distributed evenly or uniformly over the swath. Uniform distribution is desirable for a number of reasons. Included among such reasons are that uneven crop residue distribution on a field can lead to temperature and moisture gradients detrimental to even growth of future crops on the field, uneven distribution can make it difficult for crops to utilize nutrients, and uneven distribution can impact the effectiveness of agricultural chemicals. In addition, the existence of large discontinuities of spread crop residue can lead to plugging and other functional problems when such discontinuities are encountered by tillage and/or planting equipment.
One method of spreading crop residue being discharged from the rear output port of a harvester combine that has been advantageously employed has been to rotatably mount a pair of circular spreader disk assemblies side-by-side generally beneath the combine's rear crop residue output port. Such spreader disk assemblies typically have been assembled from various component parts, including a spreader plate and a plurality of separate spreader fins or bats of varying configurations which have been installed on the spreader plates to extend upwardly from the top surface of such spreader plate. The spreader fins or bats have typically been flat or straight when used for heavier residue crops, such as corn, or with smaller width grain headers, and curved when used for lighter residue crops, such as cereal grains, or with wider grain headers, and have typically been secured to the spreader plates by various hardware connectors. The assembled spreader disk assembly has then typically been operatively connected to other standard components of a spreader assembly so that, when viewed from above, the left spreader assembly would rotate in a clockwise direction and so that the right spreader plate would counter-rotate counter-clockwise.
To effect such operation, each of the spreader plates has typically been secured to a spreader cone or conical linkage that extends upwardly and axially from the top surface of the spreader plate. Extending further upwardly from the upper end of each such spreader cone or conical linkage has been a drive axle to which the spreader cone has been secured, and fixedly mounted upon the upper end of each drive axle has been an upwardly facing bevel gear. The bevel gear, axle, conical axle linkage, and spreader disk assemblies have been rotatably mounted upon the rearward end of a combine, and positioned side-by-side, and below the combine's crop residue output port.
In operation, the spreader disk assemblies have then been rotatably driven by a generally horizontal drive shaft having a leftward facing and a rightward facing bevel gear mounted thereon, the bevel gears rotating the left spreader disk assembly clockwise as viewed from above and counter-rotating the right spreader disk assembly in a counter-clockwise direction. Such counter-rotation of the left and right spreader disk assemblies has caused the spreader fins or bats to propel the crop residue rearwardly away from the harvester combine and somewhat sidewardly across the swath of the cut.
Such spreader disk assemblies must be lightweight, durable, and dimensionally stable so as to be able to operate consistently in the confined space in which they reside. Consequently, to this point in time, the spreader plates have generally been formed or constructed of aluminum for reasons of weight and flatness control, the spreader cones have been formed or constructed of light weight plastic, and the spreader bats have been formed or constructed of plastic or steel for wear resistance. Because user demands vary regarding spreading requirements, a number of such spreader disk assemblies include spreader plates that provide multiple mounting locations for a variety of spreader bats of varying configurations. By employing different spreader bats and different mounting locations, a user can effect differing spreading patterns. The versatility of such spreader assemblies, however, is tempered by the associated costs of the assemblies and their multiple configurable parts, taking into account not only the materials of such spreader assemblies, but also the varying configurations and quantities of individual components required, as well as the time required for assembly and disassembly. While many combine users appreciate the versatility of such spreader disk assemblies, they continue to seek less costly spreader disk assemblies that will still afford the quality of service that they demand.